what about this:
The focal point of the Christological argument is the person of Christ Himself. If He was who He said He was then His teachings about the authority and infallability of scripture are true. The only problem is that the most comprehensive source about Him that we have is the Bible. Therefore the Bible is still authenticating itself. To most Christians this is not a problem but to the skeptic this can be a huge stumbling block. Here is an answer to this issue in my opinion.
The greatest testament to Christ's authority and validity is in His resurrection. This act validated that He was who He said He was and testified that the His death was sufficient for the sins of man. Plus, we are able to worship a living God rather than a dead one. Now the skeptic would ask, "We only know about the resurrection from the Bible so the Bible is still authenticating itself." This is true. However, let's take a look at the human authors of the four gospels. Matthew, Mark, Luke, and John. Four different men from four different backgrounds who wrote at four different times. All of them wrote these eyewitness accounts of Jesus' life, death and resurrection. There is little doubt that their lives were changed by this experience.
Let's look at when the books were written:
Matthew - 60's AD
Mark - Late 50's - Early 60's AD
Luke - 60 AD
John - Late 80's - Early 90's AD
It's apparent that the four gospels were written during the last half of the first century but still at different times. Each of these men wrote their testimony to the resurrection and never backed off from that claim even under dire circumstances. With the exception of John, all of these men were martyred for their beliefs. They testified to the resurrection of Christ to the point of a violent death.
Matthew - suffered martyrdom in Ethiopia, killed by a sword wound.
Mark - died in Alexandria, Egypt, after being dragged by horses through the streets until he was dead.
Luke - was hanged in Greece as a result of his tremendous preaching to the lost.
John - faced martydom when he was boiled in huge basin of boiling oil during a wave of persecution in Rome. However, he was miraculously delivered from death. John was then sentenced to the mines on the prison island of Patmos. He wrote his prophetic Book of Revelation on Patmos.The apostle John was later freed and returned to serve as Bishop of Edessa in modern Turkey. He died as an old man, the only apostle to die peacefully.
The greatest testimony to Christ and His resurrection is the testimony of changed lives. These four men are just an example of the suffering and pain that Christians have endured just for proclaiming the resurrection of Christ. One could argue that people have been willing to die for false causes in the past but this many, over the last 2000 years? It seems ridiculous to think that so many would die horrible deaths at the hands of others for the cause of a lie. The only thing that would have prevented the pain and death would have been to deny Christ and His resurrection. They did not
A good testament to someone's truthfullness has always been what they are willing to risk for the truth they are proclaiming. In a court of law a wittness risks perjury if they lie under oath. For the early Christians (and even some today) they risked their very lives for the truth of Christ's resurrection. Could someone endure all this over a lie? It seems doubtfull.
If we believe the eye wittenss accounts of Christ's resurrection then we are forced to believe that Jesus was who He said He was and that His words were accurate. Jesus believed that scripture was the very Word of God and therefore infallable. Taken in this context the Christological argument for the infallability of Scripture becomes much stronger and more relevant.
Of course, to someone who is determined to be a skeptic and doubts the testimony of the martyrs, this argument can still sound like the Bible affirming itself. Christians take on faith that the gospels are accurate based, in part, on the testimony of the early Christians. However, that faith is not without it's base in fact and reason as I hope to have shown here.